Brain `geotags` memories with spatial information

Washington – A new study has shown how spatial information is incorporated into memories and why remembering an experience can quickly bring to mind other events that happened in the same place.

A team of neuroscientists from the University of Pennsylvania and Freiburg University showed used a video game, in which people navigate through a virtual town delivering objects to specific locations, to discover how brain cells that encode spatial information form “geotags” for specific memories and are activated immediately before those memories are recalled.

“These findings provide the first direct neural evidence for the idea that the human memory system tags memories with information about where and when they were formed and that the act of recall involves the reinstatement of these tags,” Michael Kahana, professor of psychology in Penn’s School of Arts and Sciences, said.

Kahana and his colleagues have long conducted research with epilepsy patients who have electrodes implanted in their brains as part of their treatment. The electrodes directly capture electrical activity from throughout the brain while the patients participate in experiments from their hospital beds.

Kahana said the finding that spontaneous recall of a memory activates its neural geotag suggested that spatial and episodic memory functions of the hippocampus are intimately related and may reflect a common functional architecture.